• Alex Elder's avatar
    soc: qcom: ipa: AP/modem communications · 530f9216
    Alex Elder authored
    This patch implements two forms of out-of-band communication between
    the AP and modem.
    
      - QMI is a mechanism that allows clients running on the AP
        interact with services running on the modem (and vice-versa).
        The AP IPA driver uses QMI to communicate with the corresponding
        IPA driver resident on the modem, to agree on parameters used
        with the IPA hardware and to ensure both sides are ready before
        entering operational mode.
    
      - SMP2P is a more primitive mechanism available for the modem and
        AP to communicate with each other.  It provides a means for either
        the AP or modem to interrupt the other, and furthermore, to provide
        32 bits worth of information.  The IPA driver uses SMP2P to tell
        the modem what the state of the IPA clock was in the event of a
        crash.  This allows the modem to safely access the IPA hardware
        (or avoid doing so) when a crash occurs, for example, to access
        information within the IPA hardware.
    Signed-off-by: default avatarAlex Elder <elder@linaro.org>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    530f9216
ipa_smp2p.h 1.21 KB